Various types of automatic blood analyzer capable of analyzing a blood sample in a short period of time have been developed and put into practice. However, collected blood is not analyzed as it is, and is normally used for a variety of analyses after the blood is diluted. In addition, for analyses with high accuracy, it is necessary to sufficiently mix the blood and a diluting solution in order to precisely dilute the blood to a desired concentration. Therefore, it is desired that the automatic blood analyzer includes a means for mixing or stirring the blood and the diluting solution. For example, in Patent Literature 1, there is disclosed a liquid mixing container for diluting a blood sample. The liquid mixing container having a roughened inner wall, contains a liquid injection port formed in an upper part thereof for feeding a diluting solution, and an air injection port formed in a bottom thereof for injecting air for stirring liquid. Further, in Patent Literature 2, there is disclosed a system for diluting and mixing a specimen such as blood by discharging the specimen and a diluting solution into a container, and then repeatedly sucking and discharging the liquid in the container using a liquid dispensing means.
On the other hand, in recent years, there has been a need to conduct a blood test easily at a home, a bedside or the like. Therefore, there is required an analyzer capable of conducting a test in a non-invasive way using a smaller quantity of collected blood without collecting a large quantity of blood with the conventional blood collection tube. However, as a matter of course, as a quantity of a blood sample is smaller, a risk of losing the sample in a process of collecting the blood or in a process of adding and mixing the diluting solution becomes higher. Consequently, it is more difficult to precisely prepare a diluted solution of blood having a desired concentration.